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Internet dragged more than half of the world's population into the cyber world. Unfortunately, with the increase in internet transactions, cybercrimes also increase rapidly. With the anonymous structure of the internet, attackers attempt to deceive the end‐users through different forms namely phishing, malware, SQL injection, man‐in‐the‐middle, domain name system tunnelling, ransomware, web trojan, and so on. Amongst them, phishing is the most deceiving attack, which exploits the vulnerabilities in the end‐users. Phishing is often done through emails and malicious websites to lure the user by posing themselves as a trusted entity. Security experts have been proposing many anti‐phishing techniques. Till today there is no single solution that is capable of mitigating all the vulnerabilities. A systematic review of current trends in web phishing detection techniques is carried out and a taxonomy of automated web phishing detection is presented. The objective of this study is to acknowledge the status of current research in automated web phishing detection and evaluate their performance. This study also discusses the research avenues for future investigation.

Among other security concerns, the reliable device to device direct communication is an important research aspect in sensor cloud system application of Internet of things (IoT). The access control mechanism can ensure the reliability through secure communication among two IoT devices without mediation of intermediate agent. Mainly, it requires twofold strategy involving the authentication of each other and session key establishment. Quite recently, in 2019, Das et al. proposed a certificate based lightweight access control and key agreement scheme for IoT devices (LACKA-IoT) to ensure smooth and secure access control and claimed LACKA-IoT to withstand the several attacks. Specifically, it is claimed that LACKA-IoT can resist device impersonation and man in middle attacks. However, the proof in this article refutes their claim and it is shown here, that LACKA-IoT is insecure against both device impersonation and man in middle attacks. An adversary just by using public parameters and by listening the communication channel can impersonate any device. Moreover, the same can also launch successful man in middle attack using public parameters and listened messages from public channel. An improved protocol iLACKA-IoT is then proposed in the paper. The iLACKA-IoT provides resistance against various types of threats and provides the required level of security, for evidence both formal validation through random or real (ROR) model as well as the informal validation through discussion on attack resilience is provided. The iLACKA-IoT is not only better in security but also provides performance efficiency as compared with LACKA-IoT and related schemes.

With the advent of the Internet of Things (IoT), there are also major information security risks hidden behind them. There are major information security risks hidden behind them. Attackers can conceal their actual attack locations by spoofing IP addresses to attack IoT devices, law enforcement cannot easily track them. Therefore, a method to trace stealth attacks is required. Conventional IP traceback methods that traceback only attackers on the network layer and cannot infer the path information of a packet traversing the switch. This article proposes a method to simultaneously traceback attack sources at the network layer and the data link layer with only one single packet. Even if the core network contains a switch or if multiple attackers launch attacks from different locations, the method can correctly traceback the true devices responsible for the attacks, and its achievements include a zero false negative rate and a low false positive rate.

The blend of Internet of Things (IoT) and social networking has introduced the emerging notion of social Internet of Things, which is bringing advancements in the operation of concerned industries. There are various prevailing applications of social internet of things; smart grid is one of them. The smart grid is considered as economical robust and intuitive replacement of the conventional grid. However, smart grid experiences two significant challenges, i.e. privacy and security. This article is dedicated to resolve the privacy and security concerns for the vehicle to grid networks to facilitate their large-scale integration with smart grids. As anticipation, a vigorous key agreement protocol is introduced to achieve mutual authentication with an aided feature of user anonymity. Moreover, efficiency in terms of computation, communication and storage needs to be taken care for resource-constrained infrastructure like vehicle to grid network. We have introduced a lightweight key agreement protocol using lightweight cryptographic operations such as exclusive-OR and hash etc. This protocol is validated through a formal security model. An informal security analysis is also elaborated to present the security strength of our protocol against well-known attacks. Furthermore, we have implemented all the cryptographic operations used at trusted agent's side on a desktop system, while the operations used at battery vehicle unit's side are implemented on an Arduino to get the experimental results. In the end, we have presented a performance analysis to compare the performance of our protocol with related ones. This comparison highlights that our protocol is not only lightweight but also efficient in terms of communication and storage cost of related protocols.

In the 5G applications, smart vehicles typically use built-in positioning functions to query geographic map information or to access location-based multimedia or service, such as traffic image, 3D graphics or surrounding points of interest (POI) from a location-based service (LBS) provider. However, when a query is submitted, vehicles’ information such as their real locations or moving routes may be collected by the service provider. To protect vehicles’ privacy, we developed a geographic map-based middleware framework to prevent the service providers from predicting vehicles’ location or moving routes by using background information derived from the geographic maps. In addition, the middleware framework uses a caching approach to generate obfuscation areas on the maps to improve performance. The proposed method also considers popular tourist POIs on the maps to enhance the cache data hit ratio and query performance.

Mobile radio frequency identification (RFID) has been extensively applied in a wide range of fields. In supply chain management, RFID is used to more efficiently manage the ownership transfer of cargo. The transfer of a group of tags belonging to multiple owners is often required at the front end of a supply chain. This study, therefore, proposes a secure, high-performance threshold multi-owner partial tag ownership transfer protocol that supports a mobile RFID environment and features the capabilities and security required for supporting existing ownership transfer environments (e.g., application for different authorities, designation of the transfer target, and ownership transfer of a group of tags). Moreover, the proposed protocol can resist against most of the known attacks on RFID.

In 2014, Yang proposed a method to enhance the current EMV credit card protocol (EPMAR). However, the protocol ignores the exceeding of a credit quota caused by multiple offline transactions, with the result that the amount spent can exceed the risk control scope. In this paper, we proposed an EMV-compatible offline mobile payment protocol with mutual authentication (EOPMA) to enhance EPMAR. In EOPMA, we use the reverse hash chain technique to guarantee the payment, which solves the problem of credit quotas getting exceeded because of multiple offline payments. During a transaction, in addition to payment for merchandise, an offline authorization certificate for the transaction is sent to the merchant. The merchant can verify the correctness of the transaction in real time. Our protocol is compatible with the EMV standard, which is applicable to the retail environment of numerous merchants and effectively, making EMV transactions more secure and reliable. We use numerical analysis to examine the security and performance of the protocols. We formally check the correctness of EOPMA by using the Gong&ndash, Needham&ndash, Yahalom logic.

E-commerce has developed rapidly in recent years and online transactions and digital services have become popular. However, existing trading systems such as ATMs, credit cards, Paypal, and prepaid systems are potentially unsecure and users' privacy is not sufficiently protected. To thus expand the applicability of e-cash systems, alternatives have become the goal of subsequent studies (e.g., offline transactions, transferability, and divisible e-cash). This study proposed an e-cash system with multiple denominations that enables e-merchants to give customers change when in an offline environment. The proposed system results in convenient transactions regardless of transaction amount and reduces the amount of e-cash users need to deposit in advance.

Display Omitted We propose an anonymous mobile payment protocol to protect users' privacy.Using anonymizing schemes to improve anonymity and unlinkability in a mobile transaction.Users can use mobile phones with NFC to perform commercial transactions. A number of mobile payment studies have been proposed in recently years. Most of the schemes are largely focused on transaction security, not on users' privacy. In this paper, we propose an Unlinkable Anonymous Payment Scheme to provide a secure and anonymous mobile commerce environment. In the proposed protocol, a user applies an anonymous virtual credit card from a trusted service manager. The sensitive information of the applied credit card is stored in the secure elements of user's mobile device. Our proposed protocol ensures various imperative security properties such as anonymity, unlinkability, and non-repudiation etc.

Traditional password-based authentication schemes are vulnerable to shoulder-surfing attacks. Attackers may steal user's sensitive information through direct observation, particularly at crowded places. In this paper, we propose a novel mobile authentication mechanism to prevent shoulder-surfing attacks. Even though an attacker can capture a user's input, he cannot derive the original password from his observation. Our authentication mechanism can be applied in various systems, especially on mobile devices. In the security analysis section, we prove that our scheme is secure against shoulder-surfing attacks, phishing attacks, and other malicious software attacks.

E-commerce has developed rapidly in recent years and online transactions and digital services have become popular. However, existing trading systems such as ATMs, credit cards, Paypal, and prepaid systems are potentially unsecure and users' privacy is not sufficiently protected. This study proposed an e-cash system with multiple denominations that enables e-merchants to give customers change when in an offline environment. The proposed system results in convenient transactions regardless of transaction amount and reduces the amount of e-cash users need to deposit in advance.

In this paper, we propose an anonymous NFC-based payment protocol (ANP) using NFC phones in a mobile payment framework. Our protocol is compatible with EMV standards, and can be integrated into an NFC-enabled mobile device serving as a virtual credit card. Each role in the framework can only gather partial user information. Our protocol achieves anonymity, in which only the bank knows a user’s real identity. TSM and the merchants are unable to break the anonymity. In a transaction, none can build up full relationship between a user’s identity and his account, his card information or transaction records.

In the supply chain management literature, various mobile radio frequency identification (RFID) protocols have been proposed for minimizing cargo theft during transport while ensuring the integrity of the entire cargo load or transferring ownership of a tagged item to another owner. These protocols are generally called grouping proof protocols and ownership transfer protocols, respectively. However, no protocol has been proposed that can achieve both requirements. In this paper, we propose a novel designated ownership transfer with grouping proof protocol that simultaneously generates grouping proofs and authenticates the consistency between the receipt proof and pick proof while ensuring that ownership of the cargo is transferred to the new designated owner in one attempt. In addition, the proposed scheme is robust against attacks (such as replay, denial-of-service, and denial-of-proof attacks) and has security features, such as forward/backward secrecy and message integrity.

To access location-based service (LBS) and query surrounding points of interest (POIs), smartphone users typically use built-in positioning functions of their phones when traveling at unfamiliar places. However, when a query is submitted, personal information may be leaked when they provide their real location. Current LBS privacy protection schemes fail to simultaneously consider real map conditions and continuous querying, and they cannot guarantee privacy protection when the obfuscation algorithm is known. To provide users with secure and effective LBSs, we developed an unchained regional privacy protection method that combines query logs and chained cellular obfuscation areas. It adopts a multiuser anonymizer architecture to prevent attackers from predicting user travel routes by using background information derived from maps (e.g., traffic speed limits). The proposed scheme is completely transparent to users when performing continuous location-based queries, and it combines the method with actual road maps to generate unchained obfuscation areas that conceal the actual locations of users. In addition to using a caching approach to enhance performance, the proposed scheme also considers popular tourist POIs to enhance the cache data hit ratio and query performance.

Near field communication has enabled customers to put their credit cards into a smartphone and use the phone for credit card transaction. But EMV contactless payment allows unauthorized readers to access credit cards. Besides, in offline transaction, a merchant’s reader cannot verify whether a card has been revoked. Therefore, we propose an EMV-compatible payment protocol to mitigate the transaction risk. And our modifications to the EMV standard are transparent to merchants and users. We also encrypt the communications between a card and a reader to prevent eavesdropping on sensitive data. The protocol is able to resist impersonation attacks and to avoid the security threats in EMV. In offline transactions, our scheme requires a user to apply for a temporary offline certificate in advance. With the certificate, banks no longer need to lower customer’s credits for risk control, and users can have online-equivalent credits in offline transactions.

Most e-rental services require customers to register sensitive information, which gives malicious service providers a good opportunity to launch social engineering attacks, or to use data mining techniques collecting and analyzing customers' information or rental preferences. Therefore, we propose an anonymous e-rental protocol based on ID-based cryptography and near field communication technology, with particular focus on vehicle rentals. Our contributions include: (1) Anonymity. Users' real identity is hidden from the rental service providers. (2) Unlinkability. Rental service providers cannot find the relation between two rental records. (3) Traceability. As full anonymity is not always desirable, traceability allows disclosure of a malicious user's identity, whereas other users' privacy remains unviolated. Rental service providers can request TTP to reveal users' identity with a legal warrant. (4) Flexibility. Users choose their preferred service providers and vehicles. (5) Anonymous payment. Rental service providers cannot associate users' identity with the financial transactions.

Text-based passwords are unable to prevent shoulder-surfing attacks. In this paper, a new authentication mechanism was introduced to send out misleading information to attackers when the former entered its text-based passwords; the latter was unable to decipher the true passwords by simply recording or looking at them. The misleading information was the pressure values (i.e., pressures exerted by the users) measured by pressure sensors embedded under the smartphone touchscreens. The systems detected each pressure value entered by the users and determined whether it was to be saved (i.e., as a true password) or omitted (i.e., as misleading information). Regarding this authentication method, because attackers were unable to know the users’ pressure values, they were unable to differentiate between true and misleading information and thus had no way of knowing the users’ actual passwords. In the end, our authentication mechanism improved the deficiency of current text-based passwords and enhanced system security.

In a secure group communication, messages between a group coordinator and members are protected by session keys. If a group’s membership changes, the session keys should be updated to insure forward secrecy and backward secrecy. Zhou and Huang proposed a key-updated scheme based on ciphertext-policy attribute encryption algorithm to improve the security of key-update mechanism, but their scheme is vulnerable: a malicious group member may send forged key-update messages to control the group. In this paper, we analyze the vulnerability in Zhou and Huang’s scheme and propose an enhanced scheme. In our scheme, only the group initiator can update group keys and the verification of key-update mechanism is improved to prevent malicious insiders from controlling the group. We also give a security and performance analysis of our scheme.

With the combination of mobile devices and readers in recent years, mobile Radio Frequency Identification (RFID) systems have been widely deployed in mobile identification. E-commerce, for instance, has applied many of mobile RFID's deriving services, one of which is the transfer of a tagged item's ownership in supply chains. However, current tag ownership transfer protocols can only transfer one tag at a time. For example, Yang et al.'s Secure Ownership Transfer Protocol is designed for low-cost lightweight RFID tags but it can only do one tag a time. For this reason, we propose a secure RFID protocol for group ownership transfer. We can transfer group(s) of tags' ownership in one attempt. Since the two supplicants involved in ownership transfer are usually under different servers' authorities, our protocol is designed to allow authority-crossing ownership transfer in a mobile RFID environment. Besides, it is able to assign its transfer targets and to secure against most RFID attacks.

In this paper, we propose an ownership transfer scheme that applies in mobile RFID networks. The scheme includes a mutual authentication protocol and a role-based ownership transfer protocol. A tag will decide what actions are allowed for a reader according to the reader's role class, and the back-end server will send to the reader the requested information about the tag. Keyed-hash functions are used to secure the protocols. Last, we prove that our protocol can do against the threats of replay attacks, distributed denial of service (DDoS), Man-in-the-Middle (MITM) attacks that change users' data, interception of data and location privacy, and tracking of tags' ownership transfer. Keywords-RFID;authentication; ownership transfer

This paper aims at analyzing the security issues that lie in the application layer (AL) protocols when users connect to the Internet via a wireless local area network (WLAN) through an access point. When adversaries launch deauthentication flood attacks cutting users’ connection, the connection managers will automatically research the last access point’s extended service set identifier (ESSID) and then re-establish connection. However, such re-connection can lead the users to a fake access point with the same ESSID set by attackers. As the attackers hide behind users’ access points, they can pass AL’s authentication and security schemes, e.g. secure socket layer (SSL). We have proved that they can even spy on users’ account details, passwords, data and privacy.

With the combination of mobile devices and readers in recent years, mobile RFID systems have been widely deployed in mobile identification and its further applications. E-commerce has applied many mobile RFID services, including the transfer of a tagged item's ownership. To secure such transfer in a mobile RFID environment, we propose a new ownership transfer protocol across different authorities. We prove that it is able to withstand most threats for RFID and prevent denial of service attacks that arise in the presence of asynchrony. It can also guarantee forward and backward secrecy, and circumvent the windowing problem. This scheme is designed for lightweight tags and has been proved to be viable for use in low-cost passive tags. It also offers better performance than any other known ownership transfer schemes.

Radio Frequency Identification (RFID) has been widely deployed for its high capabilities in simple computation, storage, long scan distance, and simultaneous reading. With the combination of mobile devices and readers in recent years, it has been transformed to mobile RFID providing wider services for its users and mobility for its readers. E-commerce, for instance, has applied many of mobile RFID's deriving services, one of which is the transfer of a tagged item's ownership. To secure such transfer in a mobile RFID environment, we propose a new approach for ownership transfer across different authorities and prove it able to stand most threats for RFID and to prevent Denial of Service (DoS) attacks that derive from asynchrony. Another contribution in this paper is that we can assign transfer targets, which, except our scheme, can only be achieved by Yang et al.'s Cross Authority Ownership Transfer (CAOT) protocol. That scheme, however, involves heavy computation and is not suitable for lightweight tags, whereas this scheme is designed for lightweight tags and has been proved viable on low-cost passive tags and has better performance than any known ownership transfer schemes. Copyright © 2011 John Wiley & Sons, Ltd. (This work was supported in part by National Science Council under the grants NSC-99-2219-E-033-001-, and by Chung Yuan Christian University under the grants CYCU-EECS.9801.)

In a flooding-based distributed denial-of-service (DDoS) attack, an adversary attempts to exhaust a target’s computing resource. To detect DDoS attacks in a network environment, IP traceback methods are deployed to determine the origin of attack packets. With the increase in bandwidth of wireless networks, attackers may choose this medium from which to launch attacks. However, tracing the attackers in wireless networks is more difficult since intermediate nodes may move or attackers may change their location to hide themselves. Thus, conventional traceback schemes for wired networks cannot apply directly to the wireless network infrastructure because the intermediate routers could be compromised by an adversary. Therefore, we propose a flexible and lightweight traceback scheme to determine the source of attack packets in a mobile ad-hoc environment. We will demonstrate our method’s ability to track the movement of an attacker and recognize attack traffic launched by the same attacker from different locations.

To minimize cargo theft during transport, mobile radio frequency identification (RFID) grouping proof methods are generally employed to ensure the integrity of entire cargo loads. However, conventional grouping proofs cannot simultaneously generate grouping proofs for a specific group of RFID tags. The most serious problem of these methods is that nonexistent tags are included in the grouping proofs because of the considerable amount of time it takes to scan a high number of tags. Thus, applying grouping proof methods in the current logistics industry is difficult. To solve this problem, this paper proposes a method for generating multilayered offline grouping proofs. The proposed method provides tag anonymity, moreover, resolving disputes between recipients and transporters over the integrity of cargo deliveries can be expedited by generating grouping proofs and automatically authenticating the consistency between the receipt proof and pick proof. The proposed method can also protect against replay attacks, multi-session attacks, and concurrency attacks. Finally, experimental results verify that, compared with other methods for generating grouping proofs, the proposed method can efficiently generate offline grouping proofs involving several parties in a supply chain using mobile RFID.

We propose a grouping proof scheme to help the nursing staff on their final check automatically before a medicine round. During the medicine round, even though their RFID reader is offline, our method can generate multiple proofs for each patient and help the medical caretakers follow the five-right policy to correctly administer the drugs to their patients. Besides, because our scheme enables a nurse to target specific group tags during a medicine round, it is able to generate proofs even when the illegitimate tags are on site. We prove that our generated proof is reliable because it can resist most security threats and guarantee the integrity of the proof. Besides, our proposed scheme guarantees anonymity on the RFID tags, so the patients’ sensitive information and location privacy can be protected. Last, we run a simulation to show that compared with the related methods our proposed scheme requires the least transmission time and the lowest computation loads to generate a proof.

This paper considers the location-tracking problem in PCS networks. Solutions to this problem in fact highly depend on the mobility patterns of mobile subscribers [ACM DIAL-M (1999) 72]. In the literature, many works have assumed a simple random walk model, where mobile subscribers always stay in a roaming state and can move in any direction with equal probability. In this paper, we propose a new Stop-or-Move Mobility (SMM) model, which is characterized by the following features: 'transition between stop and move', 'infrequent transition', 'memory of roaming direction', and 'oblivious in different moves'. Based on this mobility model, a static and an adaptive location-tracking Scheme are developed. The schemes only need to keep very little information for each user. Analyses and simulations are provided, which show that the proposed schemes are quite prospective.

One way to broadcast a popular video is to use multiple channels, each broadcasting a portion of the video periodically. Among the many schemes falling in this category, this paper focuses on several representative schemes (such as FB, Pagoda, and RFS ), which all share a FSFC property by repeatedly broadcasting the first segment of the video on the first channel. We propose a general borrow-and-return model that can be immediately applied to any scheme owning the FSFC property to reduce the viewer's waiting time without increasing the number of channels required. Given a group of videos, the basic idea is to lend the free time slots of videos without viewers to those videos with viewers to speedup the latter's transmission. By so doing, some bandwidth may be vacated by the borrowing videos to benefit others' transmission. The effectiveness of this model is analyzed by applying it to the FB scheme.

In this paper, we propose a new protocol to allow delegation transfer between offline mobile readers in the mobile RFID (Radio Frequency Identification) environment. A mobile reader can grant the access rights of a specific tag to another reader. Besides, our protocol is efficient and secure against most current network threats, such as replay attacks, Man-in-the-Middle (MITM) attacks, denial of service (DoS) attacks caused by asynchronous update, guessing attacks, and counterfeit tags. It also guarantees forward/backward secrecy, data privacy, and location privacy.

Since adversaries may spoof their source IPs in the attacks, traceback schemes have been proposed to identify the attack source. However, some of these schemes’ storage requirements increase with packet numbers. Some even have false positives because they use an IP header’s fragment offset for marking. Thus, we propose a 16-bit single packet hybrid IP traceback scheme that combines packet marking and packet logging with high accuracy and low storage requirement. The size of our log tables can be bounded by route numbers. We also set a threshold to determine whether an upstream interface number is stored in a log table or in a marking field, so as to balance the logging frequency and our computational loads. Because we store user interface information on small-degree routers, compared with current single packet traceback schemes, ours can have the lowest storage requirements. Besides, our traceback achieves zero false positive/negative rates and guarantees reassembly of fragmented packets at the destination.

One way to broadcast a popular video is to use a number of dedicated channels, each responsible for broadcasting some portion of the video periodically in a predefined way. The stress on the channels can be alleviated, and new viewers do not have to wait long to start their playback. Many approaches falling in this category have been proposed. One such scheme that interests us is the fast broadcasting (FB) scheme, which can broadcast a video using k channels by incurring at most O(D/2/sup k/) waiting time on new-coming viewers, where D is the length of the video. We consider a set of videos, each being broadcast by the FB scheme. Since the demand levels on these videos may change with time, it is sometimes inevitable to change the numbers of channels assigned to some videos. We propose a novel seamless channel transition enhancement on top of the FB scheme to dynamically change the number of channels assigned to a video on-the-fly. Clients currently viewing this video will not experience any disruption because of the transition. A channel allocation scheme is also proposed based on the arrival rates of videos to minimize the average waiting experienced by all viewers. From the system manager's point of view, the enhancement will make the FB scheme more attractive.

In this paper, we propose a new protocol to allow delegation transfer between offline mobile readers in the mobile RFID (Radio Frequency Identification) environment. A mobile reader can grant the access rights of a specific tag from another reader. Besides, our protocol is efficient and secure against most current network threats, such as replay attacks, Man-in-the-Middle (MITM) attacks, denial of service (DoS) attacks caused by asynchronous update, guessing attacks, and counterfeit tags. It also guarantees forward/backward secrecy, data privacy, and location privacy.

Based on current RFID technology, Yang proposed an offline delegation protocol in 2010, which enabled a tag's backend server to delegate the tag's access authority to a mobile reader in advance. However, there are synchronization problems in his scheme and his computation load is unnecessarily high. In this paper, we propose an efficient secure protocol to perform offline delegation, but with lower computation load and better security.

The number of spam mails has spread rapidly in recent years. Currently, the most common spam filtering solutions include blacklisting and content filtering, as well as the Bayesian approach, which uses a Bayesian filter to analyze mail content to generate classifiers. However, spammers can forge their addresses or include additional information that will mislead the filtering system or mark legitimate mail as spam instead, thus wasting the user’s time retrieving legitimate mail from the trash folder. The different definitions of users regarding spam make the filtering task even more difficult. Different to traditional filtering systems, we designed a system called. Mail Authentication Spam Filter System (MASFS) that employs E-mail authentication to allow the user to decide whether the sender is a spammer or not; this process reduces the number of spam mail and the percentage of mistaking legitimate E-mails for spam. MASFS follows the SMTP standards, which is compatible with mail servers that do not have MASFS installed, and users do not need to change their favor mail user agent (MUA); this architecture keeps the influence on users to a minimum.

In recent years the mobile RFID was developed due to its wide convenience by integrating the communication devices like PDA and mobile phone, it also directly applicable to the purchasing transaction or small amount payment. However, current RFID authentication schemes are not suitable to use in mobile RFID environment since the proposed authentication schemes result in computing load to the low cost tag and provide insufficient protection to the information privacy. Therefore, we propose a lightweight authentication protocol in mobile RFID and complied with EPC Class-1 Gen-2 norms, which effectively achieves forward security with preventing replay, Man-in-the-Middle (MITM), eavesdropping, and counterfeit tag attacks.

To protect data and location privacy of an RFID user, the transmitted sensitive information of RIFD tags must be encrypted and unpredictable. The previous approaches to protect user privacy for RFID are classified into authentication-based schemes, encryption-based schemes, and dynamic identity schemes. However, authentication-based schemes are easily broken. Because low-cost RFID tags are not tamper-resistant, the key for the authentication protocol cannot be well protected. Encryption-based schemes can protect data privacy but location privacy is still vulnerable due to fixed cipertext. Although dynamic identity schemes have chance to overcome the previous problems, but dynamic identity schemes are limited by exhaustive search problem. And, the cost of RFID tags is very limited. In this paper, we proposed a lightweight dynamic identity based RFID authentication scheme to protect both data privacy and location privacy. And we use the GNY logic analysis to show the proposed scheme can against threats of replay attacks, spoofing, man-in-the-middle, and message loss.

In a flooding-based distributed denial-of-service (DDoS) attack, an adversary attempts to exhaust a target's computing resource. To detect DDoS attacks in a network environment, IP traceback methods are deployed to determine the origin of attacking packets. With the increase in bandwidth of wireless networks, attackers may choose this medium from which to launch attacks. However, tracing the attackers in wireless networks is more difficult since intermediate nodes may move or attackers may change their location to hide themselves. Thus, conventional traceback schemes for wired networks cannot apply directly to the wireless network infrastructure because the intermediate routers could be compromised by an adversary. Therefore, we propose a flexible and lightweight traceback scheme to determine the source of attacking packets in a mobile ad-hoc environment. We will demonstrate our method's ability to track the movement of an attacker and recognize attack traffic launched by the same attacker from different locations.

This paper considers the location tracking problem in PCS networks. How a solution to this problem performs in fact highly, depends on the mobility patterns of users. In this paper we propose a new traveling salesman mobility (TSM) model, in the hope of catching the mobility patterns of a large group of users. The TSM model is characterized by features of "stop-or-move", "infrequent transition" "memory of roaming direction", and "oblivious in different moves". Then a location tracking strategy based on this TSM model is developed. The scheme only needs to keep very little information for each user. Analyses and simulations are provided, which show that the strategy is very prospective.

A VoD system is typically implemented by a client-server architecture supported by certain transport networks such as telecom, CATV, or satellite networks. The simplest scheme is to dedicate a channel to each client. Many VCR-like functions may be provided (e.g., forward, rewind, pause, search, etc.). Since video is an isochronous medium, the video server has to reserve a sufficient amount of network bandwidth and I/O bandwidth for each video stream before committing to a client’s request. Apparently, such systems may easily run out of channels because the growth of the number of channels can never keep up with the growth of the number of clients. To solve this problem, many schemes have been proposed to resolve the bandwidth problem. In this chapter, we review two kinds of broadcasting schemes. The first one is the batching scheme, in which a set of viewers arriving close in time will be collected and grouped together. Then the video server will serve them altogether with one channel. The second one is the periodic broadcasting approach. The server uses multiple dedicated channels to cooperatively broadcast one video. Each channel is responsible for broadcasting some portion of the video. Each client follows some reception rule to grab data from appropriate channels so as to play the whole video continuously. The server’s broadcasting activity is independent of the arrivals of requests. Such an approach is more appropriate for popular or “hot” videos that may interest many viewers during a certain period of time.

Current RFID authentication schemes are not suitable for use in a mobile RFID environment since the proposed authentication schemes result in a computing load because of the low-cost tag and provide insufficient protection to the information and to the privacy of the user. Therefore, we propose a lightweight authentication protocol for mobile RFID networks that complies with Electronic Product Code (EPC) Class-1 Gen-2 norms, effectively achieving forward security. We use the GNY logic analysis to show what the proposed authentication protocol can do against threats of replay attacks, spoofing, Man-In-The-Middle (MITM), counterfeit tag and message loss.

To achieve off-line delegation for mobile readers, we propose a delegation protocol for mobile RFID allowing its readers access to specific tags through back-end server. That is to say, reader-tag mutual authentication can be performed without readers being connected to back-end server. Readers are also allowed off-line access to tags' data. Compared with other delegation protocols, our scheme uniquely enables back-end server to limit each reader's reading times during delegation. Even in a multireader situation, our protocol can limit reading times and reading time periods for each of them and therefore makes back-end server's delegation more flexible. Besides, our protocol can prevent authorized readers from transferring their authority to the unauthorized, declining invalid access to tags. Our scheme is proved viable and secure with GNY logic; it is against certain security threats, such as replay attacks, denial of service (DoS) attacks, Man-in-the-Middle attacks, counterfeit tags, and breaches of location and data privacy. Also, the performance analysis of our protocol proves that current tags can afford the computation load required in this scheme.